This invention generally relates to an axle assembly and more specifically to a tag axle assembly and a method of fabricating a tag axle assembly for a motor vehicle.
Typically heavy trucks include driven tandem axles to support the weight of a towed trailer. Driven tandem axles are relatively complicated and expensive due to the need to drive each of the axles.
In some vehicle configurations it is desirable to position the driven axle to the rear of the non-driven axle to provide desired vehicle stability and handling characteristics. In such configurations the tag axle is disposed between the motor and the driven axle. Therefore, the tag axle includes a generally U shaped configuration to allow the drive shaft to extend to the driven axle. The axles include similar suspension and braking systems as compared to the driven axle.
Loads exerted on a tag axle assembly can be relatively large, which may require robust fabrication techniques, which are often not cost efficient. Further, because a tag axle does not use an axle that extends across the vehicle frame, independent spindles are used at each end. The independent spindles may be difficult and time intensive to align and may require significant reinforcement.
Current tag axle assemblies include a housing built from heavy-duty steel plate. Each spindle assembly is bolted to a torque plate. The torque plate is a separate plate bolted to the housing that provides for mounting of the spindle and brake assembly. The torque plate is secured to the housing assembly by a plurality of bolts. The connection between the torque plate and the housing is highly stressed and may require particular components that are relatively expensive to manufacture. The use of special components increases costs and contributes to inconsistencies that can affect quality.
Accordingly it is desirable to provide a tag axle assembly and method of construction that minimizes the use of expensive and complicated components.